Problems with my 94 325i

[Jason Surprise <jmsurpri@xxxxxxxxxxxxxxxx>]

I've been driving a 94 325i sedan for about 5 months now, and I've
noticed some problems which have been pretty consistent since the day I
bought it.  I'm hoping that other people on this list have run into
similar problems, and can help out.  I can't seem to find these problems
in any newsgroup posting or digest archive (although I admit I haven't
looked very hard).

1.  I have noticed that, at random times, usually when cold, and
    sometimes when at operating temperatures, that when I coast to a
    stop in neutral, that the engine cycles from approximately 500rpm
    to 800rpm.  It will keep cycling as long as the car is moving,
    but as soon as the car stops, the revs stabilize at around 6-700rpm.
    Like I said, this happens very randomly and usually during the
    morning when the car has been sitting overnight, but it has happened
    even after I've been driving for more than an hour.

2.  I sometimes have a hard time starting the car after it's been
    sitting overnight.  The engine will turn over, but it'll rev at
    around 200rpm, and the car will buck a little.  After about 5
    seconds of this, it stalls.  If I then try to start the car again,
    it starts normally.  It *always* starts normally the second try.

3.  I was recently in an accident where I was rear-ended by a truck (a
    very big truck).  My car was in the shop for about a month, and when
    I got it back, I noticed another strange idling problem.  Now, when
    I start the car after it's been sitting overnight, I notice a slight
    rough idle (I can feel it through the seat and also see it through
    the shifter).  After I drive for about a mile or so, the rough idle
    goes away.. for a little while.  After I've been driving for a
    while longer, at a random time, the rough idle will come back, and
    it'll stay for the remainder of the trip.  It is a slight rough
    idle.  Nothing that bucks the car or anything, but enough to know
    that it wasn't ever like that before the accident.  Along with the
    rough idle comes a slight performance loss, and also a very strange
    sound coming from the engine when taking off in 1st.  The best way I
    can describe it is it sounds like it is pushing more air through the
    engine than it needs.  It sounds a lot louder, almost like it is
    revving at 4000rpm when I'm only at 2000rpm.  

4.  One more problem, lately when I drive aggressively, I notice a very
    bad odor coming from the exhaust.  It doesn't happen with normal
    driving, only when I push it to redline several times in one drive.
    Odor is hard to describe.  Very rotten, but not the same rotten that
    comes with a bad catalytic, I don't think..


Well, that's it!  If anyone has dealt with these kind of problems, I'd
be happy to hear from you.

Thanks,
Jason
jmsurpri@domain.elided

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